#include <bits/stdc++.h>
#include"communication.h"
using namespace std;
#pragma GCC optimize("Ofast")
#define ll long long
#define fi first
#define se second
#define pb push_back
#define vi vector<int>
#define vl vector<ll>
#define pi pair<int, int>
#define pl pair<ll,ll>
#define all(x) (x).begin(),(x).end()
vi nums={0b0000,0b0110,0b1001,0b1111};
set<int> valid={0b0000,0b0001,0b0010,0b0100,0b0101,0b1000,0b1001,0b1010};
pi get(int a) {
pi ret={-1,-1};
for (int i=0; i<4; i++) {
if (valid.count(a^nums[i])) {
if (ret.fi==-1) {
ret.fi=i;
}
else {
ret.se=i;
}
}
}
return ret;
}
void s(int i) {
if (i==0) {
send(0);send(0);send(0);send(0);
}
else if (i==1) {
send(0);send(1);send(1);send(0);
}
else if (i==2) {
send(1);send(0);send(0);send(1);
}
else {
send(1);send(1);send(1);send(1);
}
}
int rec() {
int ret=0;
for (int i=0; i<4; i++) {
ret=(ret<<1)+receive();
}
return ret;
}
void encode(int n, int x) {
s(x-1);
}
pi decode(int n) {
pi temp=get(rec());
return {temp.fi+1,min(temp.se+1,3)};
}
